

633 

WWUS20 KWNS 270035

SEL3

SPC WW 270035

NEZ000-270700-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 223

NWS STORM PREDICTION CENTER NORMAN OK

735 PM CDT SUN MAY 26 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  CENTRAL NEBRASKA



* EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 735 PM

  UNTIL 200 AM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL TORNADOES POSSIBLE

  SEVERAL VERY LARGE HAIL EVENTS TO 2.5 INCHES IN DIAMETER

    POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 35 MILES WEST NORTHWEST OF

BROKEN BOW NEBRASKA TO 50 MILES SOUTH OF NORFOLK NEBRASKA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU3).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 222...



DISCUSSION...SURFACE-BASED THUNDERSTORM DEVELOPMENT APPEARS TO BE

UNDERWAY ALONG THE STALLED SURFACE FRONT IN CENTRAL NEB.  BOUNDARY

LAYER DEWPOINTS IN THE UPPER 60S AND STEEP MIDLEVEL LAPSE RATES ARE

CONTRIBUTING TO MLCAPE AOA 3000 J/KG...WHILE LOW-LEVEL SHEAR IS

STRONGEST ALONG THE BOUNDARY AND DEEP-LAYER SHEAR IS SUFFICIENT FOR

SUPERCELLS.  THE INITIAL DISCRETE DEVELOPMENT WILL POSE A RISK FOR

ISOLATED VERY LARGE HAIL AND A COUPLE OF TORNADOES.  LATER

TONIGHT...AN INCREASE IN THE LLJ COULD ALSO SUPPORT ADDITIONAL

SLIGHTLY ELEVATED STORM DEVELOPMENT ON THE COOL SIDE OF THE

BOUNDARY...WITH A CONTINUED RISK FOR LARGE HAIL AND A FEW DAMAGING

GUSTS AS STORMS CONGEAL INTO A CLUSTER OR TWO.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

600. MEAN STORM MOTION VECTOR 26020.





...THOMPSON

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